The goal of this project is to develop an ultrasound instrument that can identify different types of fluid that may accumulate in the middle ear space in the course of otitis media (middle ear infection). Otitis media accounts for the majority of all pediatric clinical visits and drug prescriptions. However, only a minority of these cases actually benefit from therapeutic intervention. In most cases the condition resolves on its own, and in fact antibiotic therapy often leads to resistance to these drugs. The condition that does warrant intervention is the so called "glue ear," which as the name implies involves a very thick fluid accumulation in the middle ear space. This condition can lead to irreversible hearing loss and must be treated with dispatch. Current technology does not exist to differentiate benign otitis media effusate from the viscous fluid associated with glue ear. This project will develop an instrument and transducer which can be inserted into the external ear canal and deliver a low-intensity burst of ultrasound to the tympanic membrane and the middle ear space. Various aspects of the reflected ultrasound signal, including amplitude, phase and Doppler information will be used to identify the fluid in the middle ear. Phase I of this project will identify the optimal ultrasound parameters to use for these tests, such as frequency, pulse length and repetition, and acoustic intensity. In Phase II, Spencer Technologies will develop the instrumentation to receive the signals characterized in Phase I, and identify quickly, safely and automatically the nature of the fluid behind the tympanic membrane. The value of this work is twofold: to Spencer Technologies a market potential in the hundreds of millions of dollars, and to the medical community a new clinical device which will result in improved diagnostic accuracy, rational therapy, and a reduction in health-care costs. [unreadable] [unreadable]